FIRE EFFECTS
SPECIES: Carex heliophila | Sun Sedge 



IMMEDIATE FIRE EFFECT ON PLANT : 
Sedges generally tolerate fire very well.  The season of a fire has the
greatest effect on these plants [22].  Fires usually consume dry
vegetation to ground level.  Because sun sedge is relatively leafy,
quite a bit of heat may be transferred to belowground plant parts [22].



DISCUSSION AND QUALIFICATION OF FIRE EFFECT : 
NO-ENTRY


PLANT RESPONSE TO FIRE : 
In central Alberta annual early spring burns for 25 to 30 years resulted
in an increase in sun sedge [2].  However, a study of the effect of
spring burning on vegetation in Kansas pastures showed that even though
the number of sun sedge plants increased after burning, they decreased
postfire years 3 and 4.  At the same time, the number of plants
increased somewhat on unburned areas [12].

On a mesic mixed prairie in western North Dakota with average annual
precipitation of 16 inches (41 cm), the effects of three wildfires (May,
August, and September) were studied.  After a hot, late May fire the
frequency of plants was the same or higher as that before the fire,
while a fire in late summer harmed plants [9,20].

Since mowing and grazing, as well as fire, defoliate plants, the effects
of mowing and grazing are discussed here also.  A 3-year study on a
mixed-grass prairie in southwestern North Dakota showed a greater
increase in sun sedge and threadleaf sedge (Carex filifolia) in an
exclosure than on adjacent grazed plots.  Upland sedges are considered
to be increasers; however the results of this study contradict this.
Thus, the reaction of upland sedges to grazing should be reevaluated
[3].

On the eastern edge of the badlands of South Dakota in the Pine Ridge
Indian Reservation near Wanblee, species composition of a relict
mixed-grass prairie on one mesa was compared with that of two mesas
which were grazed and mowed.  The dominant species on the protected mesa
included bluebunch wheatgrass (Pseudorogneria spicata), needleleaf sedge
(Carex eleocharis), sun sedge, threadleaf sedge, blue grama, and
needle-and-thread [7].

The protected area produced a mixed-grass association dominated by
bluebunch wheatgrass and dry-land sedges, whereas combined mowing and
grazing resulted in a short-grass association dominated by blue grama
grass.  The results of this study show that mowing and grazing greatly
reduce the amount of sedges [16].

The relationship between prescribed fire and plains rough fescue
(Festuca scabrella) and western porcupine grass (Stipa spartea)
communities in the aspen parkland of central Alberta was studied.  This
fire-climax grassland is well adapted to fire.  With settlement in the
early 1900's and the cessation of fires, trees and shrubs invaded the
prairie.  Annual early spring burns for 25 to 30 years eliminated a few
species, increased the diversity of herbaceous species, and maintained
forest cover at the same levels as presettlement.  During this period
sun sedge increased on the burned areas.  Annual burning created a drier
microenvironment than normally found on the fescue prairie and favored
sun sedge [2,16].


DISCUSSION AND QUALIFICATION OF PLANT RESPONSE : 
NO-ENTRY


FIRE MANAGEMENT CONSIDERATIONS : 
NO-ENTRY

Related categories for Species: Carex heliophila | Sun Sedge